Molecular Dynamics Simulations on Mechanical Properties of Cu-Ni Alloys with Gradient Distribution of Ni Content

Molecular dynamics (MD) simulations of nanocrystalline Cu-Ni alloys with different gradient distribution of Ni content under uniaxial tensile straining were performed to study their deformation behaviors and mechanical properties. The results indicate that, with the increase of concentration gradient of the Ni, the elasticity young’s modulus of Cu-Ni alloy increases gradually, and the yield strength and ductility of the alloy were impacted by the change of Ni content. When tensile direction perpendicular to the direction of concentration gradient, the cracks appeared in triple junction firstly after yield stage, and then in the area of Ni content close to 50 percent. When concentration gradient of Ni is very high, rich Cu area will crack easily.